EPA nominee vote coming as soon as Wednesday

That's because the Senate has up to eight hours of debate for Hochberg, though lawmakers could cut that short. But the Senate will invoke cloture on Perez and McCarthy as well, triggering up to 30 and eight hours, respectively, of debate for the nominees.

Still, McCarthy's wait to see if she will run the EPA appears to be nearing its end.

Currently the agency's top air quality regulator, McCarthy's confirmation has been in limbo since President Obama tapped her to lead the EPA in March.

The prospects of her winning Senate approval appear good, as Senate Minority Leader Mitch McConnell (R-Ky.) said last week that McCarthy likely has the support of more than 60 senators.